Zhu Ye, Gu Xiang, Xu Chao
Clinical Medical College, Yangzhou University, Yangzhou, Jiangsu, 225001, China.
Department of Cardiology, Northern Jiangsu Province Hospital, Yangzhou, Jiangsu, 225001, China.
BMC Cardiovasc Disord. 2017 Oct 16;17(1):265. doi: 10.1186/s12872-017-0695-y.
Implantable cardioverter defibrillators (ICD) are capable of effectively terminating malignant ventricular arrhythmia and are the most effective way to prevent sudden cardiac death. However, some evidences demonstrated that both anti-tachycardia pacing (ATP) and ICD shock can also bring adverse prognosis.
A 66-year-old Han Chinese man with prior ICD implantation was admitted to our hospital because of frequent ICD shocks. Although intravenous amiodarone and esmolol succinate were administered daily, the patient suffered 155 episodes of VT/VF during 8 weeks after implantation. After repeated discharge of the device, the pacing threshold of the patient increased gradually. Considering the inappropriate increase of the pacing threshold, we decided to reposition the right ventricular (RV) lead with good sensing and threshold parameters confirmed. Subsequent 22 months interrogation follow-up revealed a stable lead position and electrical specifications. Furthermore, antiarrhythmic drugs were maximally increased, while ATP burst was remarkably decreased and the inappropriate ICD shock never occurred until now.
An inappropriate pacing threshold was increased secondary to repeated ICD electrical storm. A timely active lead position adjustment reduced the pacing threshold and eliminated the risk of premature battery depletion.
植入式心律转复除颤器（ICD）能够有效终止恶性室性心律失常，是预防心源性猝死最有效的方法。然而，一些证据表明，抗心动过速起搏（ATP）和ICD电击也可能带来不良预后。
一名66岁汉族男性，既往植入过ICD，因频繁发生ICD电击入住我院。尽管每天静脉注射胺碘酮和琥珀酸艾司洛尔，但患者在植入后8周内发生了155次室性心动过速/心室颤动。在反复排出装置后，患者的起搏阈值逐渐升高。考虑到起搏阈值的不适当增加，我们决定重新定位右心室（RV）导线，并确认其感知和阈值参数良好。随后的22个月随访显示导线位置和电气参数稳定。此外，抗心律失常药物剂量最大化，同时ATP猝发显著减少，至今未再发生不适当的ICD电击。
反复的ICD电风暴导致起搏阈值不适当升高。及时主动调整导线位置可降低起搏阈值，消除电池过早耗尽的风险。
